And a certain
'echad  (ekh-awd')
united, i.e. one; or (as an ordinal) first
'ishshah  (ish-shaw')
irregular plural, nashiym {naw-sheem'}; a woman
shalak  (shaw-lak)
to throw out, down or away -- adventure, cast (away, down, forth, off, out), hurl, pluck, throw.
a piece
pelach  (peh'-lakh)
a slice -- piece.
of a millstone
rekeb  (reh'-keb)
a vehicle; by implication, a team; by extension, cavalry; by analogy a rider, i.e. the upper millstone -- chariot, (upper) millstone, multitude (from the margin), wagon.
upon Abimelech's
'Abiymelek  (ab-ee-mel'-ek)
father of (the) king; Abimelek, the name of two Philistine kings and of two Israelites -- Abimelech.
ro'sh  (roshe)
the head (as most easily shaken), whether literal or figurative (in many applications, of place, time, rank, itc.)
and all to brake
ratsats  (raw-tsats')
to crack in pieces, literally or figuratively -- break, bruise, crush, discourage, oppress, struggle together.
his skull
gulgoleth  (gul-go'-leth)
a skull (as round); by implication, a head (in enumeration of persons) -- head, every man, poll, skull.